Q.Differentiate between a prokaryotic cell and a eukaryotic cell with respect to

[!TLDR]

Prokaryotes: nucleoid (no envelope), no membrane-bound organelles, 70S ribosomes. Eukaryotes: true nucleus, membrane-bound organelles, 80S cytoplasmic ribosomes.

[!ANSWER]

1. Nucleoid vs true membrane-bound nucleus.
2. Absent vs present.
3. 70S vs 80S.

1. Nuclear region: in a prokaryotic cell, the genetic material lies as a nucleoid, directly in contact with the cytoplasm with no surrounding membrane; in a eukaryotic cell, the genetic material is enclosed within a true nucleus, bound by a double-layered nuclear envelope.
2. Membrane-bound organelles: prokaryotic cells entirely lack membrane-bound organelles such as mitochondria, ER, Golgi apparatus and plastids, since they have no internal membranes to form such compartments; eukaryotic cells possess a full set of these organelles, compartmentalising their many chemical processes.
3. Ribosome size: prokaryotic cells contain smaller 70S ribosomes (50S + 30S subunits); the ribosomes free in the cytoplasm and on the rough ER of a eukaryotic cell are larger 80S ribosomes (60S + 40S subunits) -- though the eukaryotic cell's own mitochondria and plastids still carry 70S ribosomes internally. [!ANSWER]

(i) Nucleoid vs true membrane-bound nucleus.

(ii) Absent vs present.

(iii) 70S vs 80S.

Address each of the three named points (nuclear region, organelles, ribosome size) in turn, contrasting prokaryotic and eukaryotic cells directly.

Forgetting that eukaryotic mitochondria/plastids carry 70S ribosomes even though the general eukaryotic cytoplasmic ribosome is 80S.